1. Field of the Invention
The present invention relates to a golf club head. In particular, the present invention relates to a golf club head with at least one gas cushion for effectively absorbing residual vibrations and assuring striking effect.
2. Description of Related Art
U.S. Pat. No. 5,290,036 discloses a cavity back iron with vibration damping material in the cavity. As illustrated in FIG. 1 of the drawings, the golf club disclosed in U.S. Pat. No. 5,290,036 comprises a head 100 including a striking face 101 and a back cavity 102, which is substantially filled with polyurethane 200 (or damping material). When striking a golf ball with the golf club, the damping material 200 may absorb residual vibrations and thus improve gripping comfort.
To improve striking accuracy and direction controllability of the golf ball, when the golf ball begins to contact with the striking face 101, the striking face 101 should be rapidly and significantly compressed when subjected to a slight striking stress, and the striking face 101 should rapidly resume its shape, creating a greater restoring force to be fed to the golf ball. The striking face 101 creates a rearward stress during continuous deformation of the striking face 101, which causes compression of the damping material 200.
However, since the damping material 200 has a low elastic deforming capability, in the beginning of deformation of the striking face 101, the damping material 200 overpresses against the striking face 101 and thus adversely affects the striking effect. Further, from the time of initial contact between the head 100 and the golf ball to the time the ball leaves the head 100, the striking face 101 could not effectively flex rearward to prolong the contact time with the golf ball due to overpressing by the damping material 200. Thus, the damping material 200 fails to provide the best damping effect, and the overall striking distance (i.e., the flying distance of the golf ball) decreases significantly.